| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a motor, in which an upper seal and a lower seal are closely disposed, a pressure difference between the seals can be reduced, and leakage of a lubricating oil can be easily prevented. <P>SOLUTION: The motor includes a shaft 41, a lower plate 431, and an outer tube 432. A rotation unit includes an inner tube 51 which constitutes a first gap between it and the shaft 41 and constitutes a second gap between it and the outer tube 432, and a flange 52 having a lower surface constituting a third gap between it and an upper surface of the outer tube 432, and a communication hole 61, The upper seal is constituted on the radial outer side than the first gap, and the lower seal is constituted on the radial outer side than the second gap. The upper seal is communicated with the lower seal by the communication hole 61. An area reaching to the lower seal from the upper seal through the first gap, the second gap, and the third gap, and the communication hole 61 are filled with a lubricating oil 45. A dynamic pressure bearing is formed in the first gap, and a dynamic pressure generation unit is constituted in the third gap to produce radially inward pressure acting on the lubricating oil 45. <P>COPYRIGHT: (C)2013,JPO&INPIT |
