Patent · US Expired

Disk drive actuator assembly with arm having high stiffness to mass ratio

US5978178A · kind A · utility

16Cited by
9References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 15, 1997
Grant dateNov 2, 1999
Priority date
Expiry dateAug 15, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B5/4833
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A disk drive system includes a base, a disk rotatably attached to the base, and an actuator assembly pivotally attached to the base. The actuator assembly moves the transducer to selected areas of the disk where information representative of data is to be written or read. The actuator assembly maintains the transducer in a transducing relationship with the disk. The actuator assembly includes an arm and a head gimbal assembly. The head gimbal assembly includes a suspension. The arm has a length from the point where it pivots to the end of the arm. The length of the arm is greater than 1.5 times the length of the suspension. The ratio of the length of the arm to the length of the suspension is in the range of 2.0 to 10.0. The arm is made of a composite material that includes elongated stiffening fibers. The resulting composite has a stiffness to mass ratio higher than aluminum, steel, or magnesium. An actuator arm made of the composite material having the high stiffness to mass ratio resonates at a frequency greater than 3 kHz, which is outside the operating range of the actuator servo bandwidth. The arm and the suspension can be thought of as having a fixed length for a certain des…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.