| 摘要 |
PROBLEM TO BE SOLVED: To stably provide a rolling bearing unit 4a at a low cost which is hard to bring about a fluctuation of a radial rigidity even when it is mass-produced. SOLUTION: Ball bearings 7, 7 constituting the rolling bearing unit 4a are classified in advance into two or more classes at every magnitude of the radial gap and a pair of ball bearings 7, 7 selected from the same class are fixed in between the internal cylinder 5 and the external cylinder 6 based on specified axial resonance frequency (axial rigidity) which is different from each other in respective classes. As a result, the radial rigidity of the rolling bearing unit 4a can be regulated in a desired value to solve the avove problem irrespective of the fluctuation of the radial gaps of the ball bearings 7, 7 based on a working error or the like.
|
