| 摘要 |
PROBLEM TO BE SOLVED: To provide a bearing unit that stably rotates a shaft. SOLUTION: The bearing unit 8 has a shaft 5, a bearing housing 24, a sleeve 9, an attraction magnet 25, a thrust plate 10, a ring-like member 26, and a seal washer 12. The bearing unit is internally filled with lubricating oil for smoothly rotating the shaft. The bearing housing 24 made of a magnetic material is configured such that a stepped part 30 for supporting the sleeve 9 and a small cylindrical part 28 including the attraction magnet 25 are integrally formed with each other by press working or the like. By this, a magnetic circuit is formed between the small cylindrical part 28 and the attraction magnet 25, thereby increasing the magnetic-flux density of the end face on the side of the seal washer 12 in a rotation-axis J1 direction of the attraction magnet 25. As a result, it is possible to prevent the magnetic flux coming out from the attraction magnet 25 from leaking out from the bearing housing 24. The shaft 5 made of a magnetic material is attracted to the attraction magnet 25 so as to regulate its axial movement. COPYRIGHT: (C)2009,JPO&INPIT
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