Patent · US Expired

Magnetic disc memory device

US4656545A · kind A · utility

46Cited by
8References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 24, 1984
Grant dateApr 7, 1987
Priority date
Expiry dateJul 24, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B33/148
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A magnetic disc memory device comprises a rotatable member, a stationary member for supporting the rotatable member, dynamic pressure bearing provided between the stationary member and the rotatable member, a plurality of information recording magnetic discs mounted in axially spaced apart relationship on the outer peripheral portion of the rotatable member, an annular rotor provided on the outer peripheral portion of the rotatable member in axially spaced apart relationship with the magnetic discs, an annular stator secured to the stationary member and radially facing the annular rotor, the stator and the rotor together constituting an electric motor, and a case secured to the stationary member and surrounding the magnetic discs, the rotatable member, the rotor and the stator to protect them from extraneous influence.

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