| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a bearing device for a rotation drive mechanism having reduced cost. <P>SOLUTION: The bearing device 3 is provided in a drive mechanism which is rotationally driven by a motor 20. The bearing device 3 comprises foil bearings 30, 40 provided on both sides of the motor 20 in the axial direction of a rotating shaft 21, and axial magnetic bearings 50, 60 provided outside the foil bearings 30, 40 in the axial direction of the rotating shaft 21 and having flange portions 51, 61 and electromagnets 52, 62. The bearing device 3 has protruded portions 6, 7 between a rotor 23 and each of the foil bearings 30, 40, protruded from a casing 10b, and sliding bearings 8, 9 on the protruded portions 6, 7, as protecting bearings for supporting the rotor 23. A clearance x1 between the protruded portion 6 and the rotor 23 in the axial direction of the rotating shaft 21 is formed smaller than each of clearances y1, z1 between other members. A clearance x2 between the protruded portion 7 and the rotor 23 in the axial direction of the rotating shaft 21 is formed smaller than each of clearances y2, z2 between other members. <P>COPYRIGHT: (C)2008,JPO&INPIT |
