Title :
Theoretical analysis of a ball bearing used in HDD spindle motors for reduction of NRRO
Author :
Noguchi, S. ; Tanaka, K. ; Ono, K.
Author_Institution :
NSK Ltd., Kanagawa, Japan
fDate :
3/1/1999 12:00:00 AM
Abstract :
In this paper, we theoretically analyzed the NRRO of the ball bearing caused by form errors of the inner and outer raceways and balls. The results are summarized as follows: (1) as for geometrical errors of the inner and outer raceways, it is possible to reduce the NRRO to less than 1 nm by choosing either 12 or 18 balls, even if the inner and outer raceways have harmonic undulation of less than the eleventh order; (2) the effect of the differences in ball diameter and ball form error on the NRRO monotonously decreases as the number of balls increases
Keywords :
disc drives; hard discs; harmonics; machine bearings; small electric machines; HDD spindle motors; HDDs; NRRO; ball bearing; ball diameter; ball form error; form errors; geometrical errors; harmonic undulation; raceways; Analytical models; Ball bearings; Costs; Disk recording; Equations; Hard disks; Instruments; Machining; Magnetic heads; Tracking;
Journal_Title :
Magnetics, IEEE Transactions on
