US 12,475,921 B1 · Hard disk drive voice coil motor actuator with low-density wire coil and high-density coil stiffener

Abstract

A voice coil motor assembly (VCMA), such as for a hard disk drive, includes a low-density voice coil and a high-density coil stiffener disposed inside the coil of wire. The low-density voice coil, utilizing copper-clad aluminum or aluminum wire, is configured to increase the second coil torsion mode frequency of the VCMA, thereby bringing it closer to the second torsion mode frequency of the actuator arms. In conjunction, the high-density stiffener, utilizing steel or copper or zinc, is configured to increase the mass of the VCMA to compensate for the lower-density wire in regard to the center of mass of the VCMA about its axis of rotation. In viewing under customer box vibration conditions and in terms of position error signals (PES), a non-trivial peak in the PES spectrum due to the second coil torsion mode is largely eliminated, and the power of PES is reduced to about half.

Claims20

Dependent claims

A data storage device comprising:

disk media rotatably mounted on a spindle;
a head slider comprising a read-write head configured to write to and to read from a disk medium of the disk media;
and
a rotary actuator configured to move the head slider about a pivot to access portions of the disk medium via actuation by a voice coil motor (VCM) assembly, the VCM assembly comprising:
a voice coil comprising a coil of wire, the wire having a first density, and
a stiffener disposed inside the coil of wire, the stiffener comprising a material having a second density greater than the first density.

3 more elements

Dependencies are inferred from the claim text.

Hard disk drive voice coil motor actuator with low-density wire coil and high-density coil stiffener

Life of this patent

Hard disk drive voice coil motor actuator with low-density wire coil and high-density coil stiffener

Life of this patent

Abstract

Claims20