| 摘要 |
A compound bearing assembly for a swing arm (13) of a hard disc drive is disclosed, which comprises a stepped shaft (1) having a first portion (1a) with a larger diameter than a second portion (1b), the larger diameter portion (1a) having an inner raceway groove (2a) directly formed in the outer periphery thereof. A distinct outer race ring (3) is disposed around the larger diameter portion (1a) and has an outer raceway groove (2b) formed in the inner periphery thereof. A plurality of balls are provided between the inner and outer raceway grooves (2a) and (2b), a ball bearing unit (5) having an inner and an outer race ring (5a) and (5b) and a plurality of balls (6) provided therebetween. The inner race ring (5a) is fitted on the smaller diameter portion (1b) of the stepped shaft with a sleeve-like spacer (7) between the outer race ring (3) and the outer race ring (5b) of the ball bearing unit (5). The spacer has opposite end small-diameter portions, on which the outer race rings (3) and (5b) are fitted, respectively. <IMAGE> |
