| 摘要 |
PURPOSE:To enhance the dynamic rigidity of and loading capacity of a fluid bearing unit at shaft rotating time by forming smaller bearing gap at a dynamic pressure generator at the bearing surface than the bearing gap at static pressure generator of the bearing unit. CONSTITUTION:A pair of pockets 15, 16 are cut on the bearing surface 11 of a bearing member 12 to thus form a static pressure generator, and a land portion 17 between the pockets 15 and 16 is formed as a dynamic pressure generator. A pressure fluid supply groove is cut at the land 17. Small lands 15b, 16b are projected in the pockets 15, 16, respectively with exhaust holes 25, 26 provided thereat. The bearing surface 11 is axially formed with the same inner diameter. A shaft member 13 has larger outer diameter than the outer peripheral surface 13a opposite to the static pressure generator at the outer diameter of the outer peripheral surface 13b opposite to the dynamic pressure generator of the bearing surface 11 to thereby form smaller bearing gap at the static pressure generator than the bearing gap of the dynamic pressure generator to thus enhance the dynamic rigidity of and the loading capacity of the bearing at shaft rotating time. |
