| 摘要 |
PURPOSE:To prevent seizure by employing a static pressure liquid bearing for the balancing of a rotating body for a dynamic pressure liquid bearing. CONSTITUTION:A static pressure fixed axis 22 which has a hollow thrust hole (h) and a hollow rotating axis 26 fitted onto the fixed axis 22 externally are provided in the housing formed of a lower frame 40, a table 48 for measurement, and a flank flame 38. As the rotating axis 26 rotates in a specific direction through the operation of an excited magnet 30 and a stator 36 together with a polygon mirror 28, fluid (f) flowing in the hole (h) of the fixed axis 22 from a tube 54 passes through a thrust passage 40a to press up a thrust bearing 32 in a thrust direction and then support the load on the rotating axis 26, and at the same time fluid flowing in from the hole (h) flows in a gap (c) through radial passages 22a and 22b to serve to support the rotating axis 26 radially. Therefore, the rotating axis 26 is supported in both thrust and radial directions together with the polygon mirror 28 to rotate smoothly. Further, a sensor 50 is provided on a fixed axis 22, so balance in fast rotation is kept. |
