New passive balancing algorithm for high-density hard disk drives

Abstract

Abstract

One of the major sources of vibrations in hard disk drives (HDDs) is unbalance caused by an uneven distribution of the mass on the rotational part of the HDD. Vibrations are limiting the increase in the storage density of the HDDs; therefore it is of paramount importance to identify major sources of vibrations and to reduce them to the minimum level. This paper proposes a new passive balancing algorithm which can achieve significant reduction in the HDD unbalance at low cost and with a high yield rate. The unbalance reduction is achieved using a balancing ring with a large number of holes which are used for the placement of balancing masses of a given weight. The optimum number and position of the balancing masses is then found in order to reduce the residual unbalance to minimum level. Guidelines on optimum selection of the correction mass are also proposed.