| 摘要 |
A plurality of grooves (111) extending from axial-direction ends are formed on the inner circumferential surface (105b) of an inner ring (105). The grooves (111) extend axially inwards from both axial-direction ends of the inner ring (105), and are closed at axially intermediate positions of the inner circumferential surface (105b) of the inner ring (105). The grooves (111) are formed in a plural number at equal intervals in the circumferential direction. |
