Compact bearing

The antifriction bearing (B) fits around a journal (6) at the end of an axle (A) for a rail car. The journal (6) extends from an intervening section (4) of the axle (A), and the intervening section (4) in turn projects from a still larger main section (2), there being fillets (8, 10) where the sections merge. A backing ring (20) fits against the fillet (10) at the end of the journal (6), while an end cap (24) fits over the opposite end of the journal (6). The bearing (B) includes two cones (32) which are clamped between the end cap (24) and backing ring (20), a double cup (30) surrounding the cones (32), and tapered rollers (34) arranged in two rows between raceways (46, 42) on the cones (32) and on the cup (30). The ends of the bearing (B) are closed by seals (36) which are fitted to the cup (30) and cone (32). The thicker intervening section (4) of the axle (A) is extended in comparison to its counterparts on traditional axles, and the backing ring (20) extends axially along the journal (2) generally no further than the location at which the fillet (10) emerges from the main body of the journal (6). This presents the back face (54) of the inboard cone (32) in a region where the journal (6) is quite stiff, thereby reducing flexing and fretting considerably. The inboard cone (32) is undercut at its back face (54) so that the stress concentration produced at the end of the interference fit between the inboard cone (32) and the journal (6) does not coincide with the stress concentration that develops at the fillet (10) around which the backing ring (20) fits.