Search

In this paper, we propose a novel shockproof head gimbals assembly (HGA) structure incorporated with 'a balanced-type head suspension' for 0.85-in hard disk drives (HDDs), and investigated its performance on external shock resistance during read/write operations. Experimental drop impact test results confirm that the 0.85-in drive equipped with the new suspension structure is durable over 2000 G (1.0 ms duration) of external shock, ensuring no head slider and/or disk surface damage. According to computer simulation and experimental results, potential shock resistance of more than 2000 G may also be possible with the head actuator itself, which points to its application in cellular phones. Index Terms--Balanced-type suspension, drop impact test, external shock resistance, hard disk drive, head gimbals assembly, impact acceleration, mobile use, shock-proof.

A new on-line methodology has been developed for both evaluation and analysis of head/tape interface phenomena. It uses the direct relationships between the power in the acoustic emission (AE) signal and wear, and between the power in the AE signal and the normal force acting on the magnetic head. The AE transducer is directly mounted onto the head assembly of a VCR mechanism in order to measure the head/tape contact behavior. This technique has been used to: (a) monitor the effect of relative humidity on head wear; (b) investigate the wear characteristics of Mn-Zn ferrite as a function of crystallographic orientation without direct measurement of the wear volume; and (c) evaluate tape abrasiveness. Explicit correlations were also obtained for the normal force acting on the magnetic head, the tape wrap angle around the head, and the reproduced signal flatness in terms of the tape transverse stress distribution. Moreover, the normal force as a function of the tape stress distribution is closely related to the longitudinal tape vibration at the head exit region.