| 摘要 |
The rotor (29) comprises the tubular shaft (30) which is supported by the bearing (28) of which the outer part is integral with the stator (21). Said part (30) is machined with an inner cylindrical surface (31) and an outer cylindrical surface (32) which both extend throughout the length of the part. Both said surfaces may be machined with all the precision required during simultaneous or successive operations without loosening the part which is preferably held by its end opposite to the surface (33) in the clamp of a machine tool. Thereby, the assembly tolerances as to the eccentricity of the recording medium with respect to the stator of the motor which are of the order of 1 mu m may be easily respected. |
