Recording disk drive unit
US4620301A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 19, 1983 |
| Grant date | Oct 28, 1986 |
| Priority date | — |
| Expiry date | Dec 19, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K41/025
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A turntable for placing a recording disk such as an optical information storage disk has a rotatable shaft to which an electrically conductive rotor is fixed. Inner and outer stators are disposed in confronting relation to each other with the rotor interposed therebetween. Each stator has a C shape with a recess in which there is placed one end of a radial feed unit for moving a pickup head radially across the turntable for recording information on or retrieving information from the disk on the turntable while the latter is being rotated. The outer stator comprises a comb-shaped block having a plurality of teeth with coils wound thereon in different phases. When sinusoidal currents are supplied to the coils, the stator produces a moving sinusoidal magnetic field to rotate the rotor according to the principles of a polyphase induction motor. The rotor may double as the turntable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.