| 摘要 |
PURPOSE:To enable the durability of bearings to be enhanced, by forcibly feeding lubricating oil into the clearance between outer spacers/outer rings and a housing to reduce the additional weight to a rotating body in the high-speed region. CONSTITUTION:In a low-speed region, the oil film layer formed in the clearance between a housing 20 and outer rings 3B, 4B or outer spacers 22, 23 is not perfect, and the radial load is supported by rolling bearings 3, 4. In a high-speed region, since the pressure of oil supplied in the clearance between the housing 20 and the outer rings or outer spacers through ring-shaped grooves 20B, 20C becomes high, sufficient oil film layer is formed. Accordingly, the fluid friction due to the oil film layer becomes relatively less than the rolling friction, and the outer rings 3B, 4B and outer spacers 22, 23 rotate in high speed integrally with a turning shaft 2, thus the additional weight is reduced to enhance the durability of bearings. |
