| 摘要 |
<p>PURPOSE:To prolong the extent of service life as a thrust bearing by forming a cylindrical part in one side of both ends of the inner tube of a rotor and the central shaft part of a stator, and a small diametral part being fitted in this cylindrical part in the other part, respectively, and keeping off any radial extension of a circular seat set up as a thrust bearing. CONSTITUTION:A cylindrical part 10a is formed in the end of an inner tube 10, and a small diametral part 4a being fitted in this cylindrical part 10 is formed in the end of a stator central shaft part 4. A gap X between an inner surface to the cylindrical part 10a and an outer surface to this small diametral part 4a is formed to be smaller than thickness (t) of a circular seat 14 or a thrust bearing, and a peripheral edge of this circular seat 14 is made so as not to get into the gap X. In addition, wall thickness of the cylindrical part 10a is thickened and its depth is deepened, and an area of a fitting surface between the cylindrical part 10a and the small diametral part 4a and each sectional area of these elements 4a, 10a are all formed into such that there is sufficient room for passing a magnetic flux to be produced by a magnet coil, through which it is unnecessary to set a bearing surface, where the circular seat 14 exists, down to a magnetic passage, thus the circular seat 14 is thickened and, what is more, thrust load can be made smaller as well.</p> |
